Process of converting fibrous plants into textile fiber and pulp.



I Y F. RSTRONG. PROCESS 0F GONVERTING FIBROUS PLANTS INTO TEXTILE FIBER AND PULP.'

PPLIOATION FILED JUNE 10. 1910.

I Patntea oct. 10, 1911.

I l l l l l I r l YW/M 1. P. STRONG. PROESS OF'GONVERTING PIBROUS- PLANTS INTO TEXTILE FIBER AND PULP. I APPLIUATION FILED JUNE 10, 19101 I 1,005,354@ Patented 001. 1o, 1911.

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j(- 1 I i 1 tmrTED i STATES' PATENT 'omrica.y i

FREDERICK E. STRONG, 0R sT. PETERsnUInG, ILGRIDA.'

`rRooEss or coNvERTrNe FIBRous PLANTS INT0 TEXTILE FIBER AND PULP.

i Specification of Letters Patent.

Patented Oct. 10, 1911.1.

Application aledaune 1o, 1910. serial No. 565,220.

of St.v Petersburg, in the county of Hills-4 boro and State of Florida, have invented an Improvement in Processes of Converting Fibrous Plants Into Textile Fiber and Pulp, of which the following description, in connection with the accompanying drawings, is a specicatiou, like letters on the drawings representing like parts. 1

In .the tropics there is ar vast amouutof unutilized librous material, which itis the object of my present invention to make practically available for the manufacture of paper, textiles, artiiicial hard rubber, artiicial ivory, vulcanized fiber, etc- While my invention is not limited tothe utilization of the tibi-ous plants of the tropics, but can be -applied to various other approximately similar plants and growths, it is particularly intended for the product-ion of crude paper pulp, text-ile audcordage fiber,

,etc., from the leaves, leat'fstalks, stemsheaths, trunk-wood, and roots of such pracof supply as the cabbage palm or pahnetto tree, the saw palmet-to or scrub palmetto, the everglade' saw-grass (which at present are notused at all); the century plan-t, the plantains, New Zealand liax, Ada'ms needle, Spanish bayonet (at present used only for coarse cordage fiber); the pineapple and the banana (at present grown for their fruit but otherwise not put to use). I have succeeded in developing the hereinafter described mechanical and'chemical process whereby the somewhat coarse natural fibers of the plants are easily broken up into line White bers suitable even for spinning into fabric having the wearing qualities of linen and the luster fof silk, and the cellular tissue is converted -into a. valuable pulp-product from which l,tough paper may be produced, as Well -as other articles hereinafter mentioned. All these trees and plants contain long-parallel fibers or bundles of fibers rnn'uinocontinuously from root through trunk, lleaf-stalk,

and leaf, the large stalk bundles in. some cases sepa rating in the leaf into radiating smaller bundles, and it is one object of my process to isolate these fibers without. breaking them or lesseniug their strength. These fibers in their natural state are 'contained in.

masses of pulp 'cells or parenchyma containing green chlorophyl granules andeellul'ar skins or laminarJ of a tough and dense character, bound together by' natural cementives.

My invention has for one object the dissecting or separation of the fibers mechanically so as to avoid slow rotting and Weakening processes (my p rocess preserving all the natural strength of the-fibers), and the .separation of the pulp-material in such a way as not to completely remove the natural resins (leaving the latter in proper amount.

to self-size the. paper,- =ete), and to bleach 'and treat this pulp-materlal without subjecting the same to the usual strong chemicals and severe action which, in the case of sultite pulp as commonly made, tends to weaken the liber.

' The details of my invention will be more readily and fully understood with reference to t-he accompanying drawings illustrative' -of a. preferred mechanism for carrying out the process. Y

In the drawings, Figure lis a vertical longitudinal sectional vlew of the entire apparatus, parts being-in side elevation and parts being-,broken away for clearness of illustration; Fig.- 2 is an enlarged detail in front elevation of the dissector WheelpFig. 31W is a. perspective view of a leaf-stalk showing the bers thereof mechanically dissected by my process; Fig. 4 is a ton plan view of the eleetrolytic port-ion of the apparatus; and Figs. 5 and '6 are views to illustrate the cathodic electrolytic action which presumably takes place on a. bundle of fibers andv tissue as seen under a microscope, Fig. 5 showing the bundle before 4the action of the current and Fig. 6 during s'a-ifd action.

In handling the plants by my process, the raw material (leaves and stalks) is brought to the millin largeloudrat scows, from which it is automatically discharged over a lowbreakwater into acollecting pool of salt' water. Thence the material is lifted by. any' suitable means, as by a belt 'conveyer, to a hopper l whose bottom extends forward to constitute a table 2 along 'which' the fibrous material isfed endwse by a spiked or toothed feed drum or roll 3 beneatha compressing feed wheel 4 to a dissector wheel 5.

While various mechanisms. may be provided or accomplishing the dissecting raction of the plant fiber, and therefore the particular form 'of dissector herein shown is not essential, it is essential thatthe dissecting'step in, the process-shall befully and l clearly understood, asl regard the same as one oftlieimost important-ifeatui'cs `O f'ithe invention. Instead 0f rotting or otherwise I -chemically"ldisintegratingor partially vdisintegratin'vfthe. plantber, it is treated in 1ts natura s tgl'teas" 1ndicated for instance at 6,"F1g.'3,;b e1ng fed'cndwise to 4a whipping, slitting, combing, rubbing, and washing device, with the result that the pulp `tissue is mechanically removed from about the individual fibers, leaving the latter projecting like 'a fringe, as shown at 7, Fig. 3.

As the plant, stalk, leaf, or other raw niaterial 6 is 1n its naturalstate, 'the result -is that the fibers arenot weakened Lbut retainl their natural strength, length,'and structure. I regard the cleaning of the fibers mechanically, asdist]ngulsluxl-from a,.rotting proc-v with a multitude of parallel slits inadethere' .through dissimultancousl f 'a few at a time @1n such numberA -that there is no liabilityof tearing or breaking the fibers, and yet 1n dissector 5, as herein shown, comprises a` series of rolls 8, each consisting of a phirality of-thin, knife-like disks 9 'mounted on a shaft 10, as best shown in Fig. 2, the disks of v the successive rolls being offset slightly in staggered relation ,to each other so that, in the course of one complete.v rotation of the dissector 5, each disk will make its ownindividual cut through the fiber j ustout of the pa th of all ofthe corresponding preceding disks..

Thus, as herein shown, as there are six rolls 8, t-lierewill be six cuts in --the stallcend in thespaccv of. two adjacentdisks, said euts,

' however, being made onlyone 'at a time. .By

this V'means the stalk is cut-practicallyas closely as the fiber'sareto each' other, and

-yet this cutting takes .place .with an entire freedom of movementand.absence of pulllng or iiearmg' tendency on the stalk because only part ofthe cuts are made at one time,

` viz. thosecuts which correspond to the disks in further separating-the Hbcrs and ,combof any one roll 8.: Between theA disksare combs 11V which cooperate With the disks rabainto vsmall '-,lengths' sof that. afall down into' a receptacle .13 along' with the sepa- .rated pulp matter; When, however, the

otherwise removed from the stalk or plantmaterial, is caught in the receptacle 13, jets l 'of salt water.l from a. transverse pipe 18 80 vbeing driven'against the fringed en ds of the 1 'plant-nmtI-.ujial as it is being cut combed, and cleaned,ai.1 d'in this receptaclell it' is thor# 1 foughlymined' and Washedby an agitator "19 in thest'rong saltwateri'solution 20 con?" g5 tained in saidrecept'acle, thereby removing` much of the microscopic chlorophyl granules and also soluble pigments and finely divided 'debris which rise toward theV surface and` pass through a-fine' wire screen 21. and out 90 to evaporating and settling tanks for further refining in the production of minor by-prod.-

vucts such asresins, gums, alcohol, oilspetc.

The material leftin the receptacle, having been freed from its green juices and chlo-` 95 rophyl, consists of nearly pure tough cellulose, admirably adapted for the production of paper pulp and various other articles.V

'By my process. this cellulose mass reaches this finely divided condition in a chemically `uninjurcd condition, inasmuch as practically its only treatment has been mechanical, so thatitstough character still remains (as 'distinguished from the common methods of producingT pulp), and also lit is' in a condi-A v105 tion easily reachedand acted upon by any chemical agents used `for refiningr and-bleaching it. y

The importance of my process the re spe'cts noted will be more apparent whent no lis borne in. mind that I have succeeded in eliminating 'the special digester treatment and all the' usual steam vor otherheattreat-:i ment heretofore 'considered essential for'.

treating the plants most nearly alliedto those heretofore enumerated, 'such'as are used for the. manufacture of book and Writing papers. I take thegreen plants directly from the saltwater pool, and.' by rapidly l cutting them longitudinally along the lines 12d `if 'least resistance into a fine fringe in. 'the :presence o f contrnuousgpushlng rubbing,` l'

1.whipping .ction .and'je't's of washing-Water,

convert fplantsf intoeitherseparated A fbodicsfof fiber and of pulp. tissue or into a 1-25' "provided to copatc'wvitli theffcnd of the table 2, which in .Siach-instancegismade of steel, in chopping or shearing-oflfy the tibet-s combined fiber and pulpmass ofsuch a naf- -ture .that the' desired. tine' pulp 'can be ob- 'tiaincd therefrom v'simply by .soaking the mass in'a cold mechanically agitated solution, preferably of salt. After the separa- 1st tion in this salt .solution of the coloring matter from the pulp body as stated, the latter, vhaving settled to the bottom of the receptacle 13, is drawn through the foraminous bottom 2 2, preferabl f by a rotating plate 23 provided on its upper side with grooves r passages 24 which squeeze out, rub and grind the pulp to sonic extent as said plate the-shaft of the stirrer 19.

ber 2G, Where it is mixed with a strongl solution of common salt, additional solution heing admitted when required at 27' The pulp mass, having become thoroughly'impregnated with the salt solution, flows through a pipe 28 to the electrolytic bath. In a tank 29 partially filled with a suitable electrolyte 30, such as salt solution, l provide two pulp-solution conveyers 3l, 32,

each composed of porous material such as clay or unglazed porcelain, preferably in` cludmg a series of vertical gars 33 for more conveniently holding the carbon electrodes 34. The terminals 35 of the electrodes in .the conveyer -31 are connected in parallel to the negative or cathode side of a source of surface, so that the' cathodic -tween the Icells and fibers 0de 35, and being carried energy 36 by wires 37, and the terminals 38 of the electrodes in the other conveyer 32 are connected in parallel to the positive or anode sideA of the source of electric current by Wires 39. V

Negativeelectrolysis of the saline solution occurs in intimate relation with the suspend ed pulp elements passing from pipe 28 through conveyer 3l. The salt-osmotically penetrates toy a certain extentin and be- (during their maceration in strong brine in the receptacle 20) Which pass close to the surfaces of lthe cathor suspended in a the brous masses beextensions of 4the `cathode products, viz. hydrogen gas bubbles and caustic soda, are liberated in intimate relation with the ele- Weake'r salt solution, come, 1n a sense,

` ments of the fibrous material, the bub- `chemically weakening said material, andthe second being the fact that the'aeti ve power of the slight chemical agent used isz normally increased by beingliberated in an approximately nascent condition. V

It is to be especially noted, also, that my 'excepting that in the process makesit practicable to partially saponify the oils and resins, as distinguished from entirely eliminatinT them. Because of the absence of heat, and the predominance of mechanical treatl'uent, I am en` abled to effect this partial removal of the resins sothat enough resinous material is left to size the paper when the pulp is passed under the heat rolls of the paper muchine. rl`his is especially true with pallnetto stock, which is unusually rich in resinous material.

After passing through the conveycr 3l, the now extremely fine pulp passes to a settling tank 40, where a stirrer tl washes the fiber approximately clean of chemicals, fresh water being introduced at 42 and the wash water drained off at 43, and thence the washed pulp passes to a collecting tank Lifi, where it receives a fresh supply of strong salt solution from a pipe. 45, and is then raised through a pipe 46 by a pump 47 and forced forward through a pipe 4.8 into the pulp conveyer 32, where the nascent chlorin evolved at lthe anodes blcaches and whitens the pulp and dccolorizes any remaining` green matter retained in the pulp cells.

It should be noted that the elements of the pulp produced by `my process from the raw materials mentioned in the pri-iceding pages, consist of practically colorless cellu` lose, and the bleaching process can be carried out more quickly andin a. weaker chlorin solution, than with any other variety of pulp at present employed in making` paper, inasmuch as the only elements to bc decolorized consist of chlorophyl granules mechanically entangled or retained in the pulp material.

After passing from the conveyer 32 through the out-let pipe 49, the pulp is washed in freshwater, run yinto sheets on a cylinder machine, dried, baled, and shipped to the paper mills, or it can be run into a beating engine, and trcated'so to be at once formed -into paper without intermediate drying, or it can be made into artificial hard rubber, ivory, vulcanized liber, or the like by any of the well known pressure and-- eat processes. ln other words, the stock is of such a pure character and so finely subdivided that it is ready for general use.

The process is the same Whether pure pulp being treated or the fibrous stock,

latter case the conveyors 3l, 32 are preferably not tortuous but are straight for the better handling of long hanks of liber. The disruptingfetfect of the cathode elei'ztrolysis is the same as already described, the relatively coarse fibers being broken up into'small iibers which are fine and silky and suitable for spinning, and after bleaching, .are dried in centrifugal dI- irs and baled 'for shipment to the textile mi s.

When my process is used in the separation of hemp or' cordage fibers, the latter are Washed and baled after coming from the dissector, and are not given the alkaline bath or electrolytic treatment. It will be understood that the latter part of the process is used where it is desired to subdivide the stock beyond its JL.ructural subdivisions, and where it is desired to bleach the product, as in making paper pulp. As the stock or pulp mass passes in, a continuous stream through the cathode jars, it is refined both mechanically and cheniically,Mmechanically by the agitating action ol" the liberated hydrogen, andcheniically by the caustic soda generated, as above described I have already mentioned various advantages of the pulp made by my process. Another peculiarity is the readiness with which the pulp parts with its water on the paper lmachine, and its relatively non-hygroscopic character. ln other papers, the prolonged treatment in' the beating and refining engines not only breaks up the ultimate fibers, but renders theni water-soaked and boggy, so that great difliculty is experienced in fiiee- ,ing ordinary papers from their -water content. My process deals primarily with raw materials in which the fibers are pointed with the very small lumens naturally closed,

and a sufficient amount ot the natural resin being retained to render the web practicallynon-h'ygroscopic. ln other words, njiy j process the pulp never becomes water-soaked so that there is not so much -water to bc re! moved, ,andA it is always maintained 1u "it somewhat water-repellent'condition so that it parts with mechanically held-water at once on the paper machine. Paper pro` duced from pulp made by my process is also extremely 'light inweight, and it felis so readily and intimately that longer fibers L vhmay be used in Aiiirniirig the pulp thanY in other processes, thereby giving the resulting vpaper the'durability ol a finely woven tabric. By suitable treatment, this paper. or convei'l'edpaper can readily be used for clothing,'as it can be cut andsewied the same as woven fabric., As only its surface will soil readily, it, 'canbef cleaned. with a damp cloth As already stated, the pulp is adapted tovarious other uses than paper, and the separately removed fiber is Before entering upon the clectrolytic portion, of -the process, the pulp or prepared iso vcally into the walls oi2 the cells and fibers,

in which the salt .solution replaces by capii,

-larityvthe juiccswhipped out in the dissector.1 .Having thus filled the iiiaterialwitli 'the strong-salt solution, itis suspended in adapted to various other than textile uscsl`- a weaker salt solution and then conducted through the elect-rolytic channels. As a strong salt solution is a better conductor of electricity than a Weak salt solution, it results that as the fibers thus impregnated with salt are conveyed in a weaker salt solution through the conveyor 3l, the electric current, choosing the best conductor, follows the path of least resistance, vin `the salt-impregnated fibers, or in other Words spends its electrolytic efficiency in the mechanical disintegration and chemical disintegration of the fibrous elements, as previously eX- plained-in detail. Vhen so saturated the saine cells part with their salt very slowly, and as the weak brine is only added just before the pulp passes through the cathode channel, it follows that the bits of salt-saturated pulp, brushing against the surface of the cathodes in their passage through the porous conveyers or channels become in ell'ect s po'ngy extensions or brain hes of said cathode, and the electrolysis therefore actually does occur within their inte'istices. Thereupon the mass is Washed thoroughly free of its caustic soda before being subjected to the bleaching process. Thisis necessary in order that the bleaching process may be effective. Having been Washed thoroughly and thereby freed oit its caustic soda, the cleaned fibers are again impregnated with a strong salt solution, so that when it then, passes through the bleaching conveyer the electrolytic action is primarily a bleaching action. .The olilorin expends itself in bleaching .the liber rather than in combining with any lrce alkali, which would be the casev from the smaller fibers of the plant-material,

intel-mixing with the stock thusobtained a salt solution, and then as a continuous prorefining the mixture while in said solution.

Q. The herein described proccss,-consist ing ot mechanically dissecting the cellular tissue 'ti-om t'hc smaller fibers 'oit the plantmaterial. .interiiiixing with the stock lthus obtained and as tast as dissected a saltsolu v tion, and immediately elcctrolyti'cally retin?v .110 eeeding with the Vforegoing electrolytically ing the mixture while in said solution and then at -once electrolytically bleaching the refined product all being conducted and proceeding continuously,

3. rl`he herein'described process, consisting from the smaller fibers ofthe plant-material,

inlermixing kwith the stock thus obtained a said solution and immediately and as a e011-,

tinuous procedure further refining the pulp material in the presenceof caustic, soda.

4. The herein described of subdividing the plant-materialcold and only partially removing the natural resin therefrom.

5. The herein described process, consisting of mixing the pulp mass with 'afsalt solution, i

retaining an appreciable part of the natural resin, mixing'the 'pulp body .Wit-ha cold salt solut1on,caus1nglthe same to How, and subjecting the tlowing cold mixture to a cathode electrolysis.v f l 7. rllhe herein described process, consisting of mixing the pulp body `with a salt solution, causing 'the same to vflow, subjecting' the iowing mixture to a cathode electrolysis, then separating to a greater or less extent the chemicals from the pulp body, subjecting the latter again to a salt solution, and passin the same through an` anode electrolytic bath'V whereby the pulp is bleached by the nascent chlorin gas thus generated, all the fore-f i going proceeding continuously.

.8. The herein described process consisting of mixing the p`ulp mass with a salt solution, and subjecting the same to. Acathode electrolytic action, liberating bubbles of hydrogen gas at the cathodes among the smaller fibers vand` cell masses of the pulpbodywhich are againstsaid cathodes to .assist in mechanicaliy bursting apart and disrupting the same, and forming caustic soda for the further isolation of the cellulose ultimates,

process, 'consisting then immediately Washing the massethoroughly free of its caustic soda prior to bleaching, and then impregnating the clean:

fibers With a strong salt solution and subj ect-ing the same at once to anode electrolyti/c' action.

9. The herein described process consisting of impreiinting the pulp 'body With a strong 'salt solution, and at once'suspending the strongly impregnated pulp body in a weaker salt solution and subjectingthe same to cathode elcctrolytic actionl for mechanically and chemically disintegrating the fibrous elements, continuouslyprogressing the mass through the foregoing and then through a Washing process'until the fibers are thoroughly free of theca'ustic soda, and thereupon at once again impregnating the bers With a strong salt solution and subjecting this impregnated massJ to anode elctrolytic action.

. 10. The herein described process consisting otiimpregnating the pulp body with a strong-'salt solution, and'at once suspending the .strongly impregnatedpulp body in a weaker salt solution and subjecting the same to' cathode' electrolytic 'action for 'mechanically andv chemically disintegrating the fibrous elements, continuously progressing the mass through the foregoing and then throughva Washing process untill the fibers ,are thoroughly free of the caustic soda, and

thereuponlat once again Vimpregnating the fibers with a strong salt solution and subjectiiig this impregnated mass to anode electrolytie action, all the foregoing being done cold, I

In testimony whereof, I have signed my name to this specification, in t-he presence of two subscribing Witnesses.

FREDERICK F.- STRONG.

. Witnesses l i GEO. H. MAXWELL,

M. J. SPALDING. 

